From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9C6A0C7618B for ; Thu, 25 Jul 2019 06:35:39 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4E43021901 for ; Thu, 25 Jul 2019 06:35:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="n1pZKKAD" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4E43021901 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=jteqJt5h0VxcTe+CctmEPj0OYOig7QB2/njMUQrOnIs=; b=n1pZKKADFws4tz JqKr/bJ8N4SfjehO2TuvVQiXnKSpkQ4H9bn0FUDzfjRTOPgEFFxQUmCt4+KAFNcDJn227n/uVOQE2 gK3FJ5UcrTZuvboEfbKnEqXj28+h/PInCV2pjDE36QxT8W6USPsf48KYEgAD9EFRYr/1S9xx5cSDl nA3s3uBgLuoXm6dC8dVKZM6t2ycd83o1D8Qe2YiiZ5+3kI9LWnXPQvi6uBVbpJ2y4puoX3QOE6eYY 3YK9VLPv+fHXBmn2VSdoKRxBRQNUq26gRizmHh9Ck7E9qN4qiFLIpQYEgcvQ5EVb3mtwS1hs22E+Z 8nLGEMoPnuF0PBTaW8aQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hqXLm-0002XN-MZ; Thu, 25 Jul 2019 06:35:38 +0000 Received: from p57b3f613.dip0.t-ipconnect.de ([87.179.246.19] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92 #3 (Red Hat Linux)) id 1hqXKR-0000KM-CH; Thu, 25 Jul 2019 06:34:15 +0000 From: Christoph Hellwig To: iommu@lists.linux-foundation.org, Marek Szyprowski Subject: [PATCH 4/5] dma-mapping: provide a better default ->get_required_mask Date: Thu, 25 Jul 2019 08:34:00 +0200 Message-Id: <20190725063401.29904-5-hch@lst.de> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190725063401.29904-1-hch@lst.de> References: <20190725063401.29904-1-hch@lst.de> MIME-Version: 1.0 X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-xtensa@linux-xtensa.org, Michal Simek , linux-parisc@vger.kernel.org, linux-sh@vger.kernel.org, Takashi Iwai , linuxppc-dev@lists.ozlabs.org, x86@kernel.org, linux-kernel@vger.kernel.org, linux-m68k@lists.linux-m68k.org, Robin Murphy , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Most dma_map_ops instances are IOMMUs that work perfectly fine in 32-bits of IOVA space, and the generic direct mapping code already provides its own routines that is intelligent based on the amount of memory actually present. Wire up the dma-direct routine for the ARM direct mapping code as well, and otherwise default to the constant 32-bit mask. This way we only need to override it for the occasional odd IOMMU that requires 64-bit IOVA support, or IOMMU drivers that are more efficient if they can fall back to the direct mapping. Signed-off-by: Christoph Hellwig --- arch/arm/mm/dma-mapping.c | 3 +++ arch/powerpc/platforms/ps3/system-bus.c | 7 ------ arch/x86/kernel/amd_gart_64.c | 1 + kernel/dma/mapping.c | 30 +++++++++---------------- 4 files changed, 14 insertions(+), 27 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 4410af33c5c4..9c9a23e5600d 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -192,6 +193,7 @@ const struct dma_map_ops arm_dma_ops = { .sync_sg_for_cpu = arm_dma_sync_sg_for_cpu, .sync_sg_for_device = arm_dma_sync_sg_for_device, .dma_supported = arm_dma_supported, + .get_required_mask = dma_direct_get_required_mask, }; EXPORT_SYMBOL(arm_dma_ops); @@ -212,6 +214,7 @@ const struct dma_map_ops arm_coherent_dma_ops = { .map_sg = arm_dma_map_sg, .map_resource = dma_direct_map_resource, .dma_supported = arm_dma_supported, + .get_required_mask = dma_direct_get_required_mask, }; EXPORT_SYMBOL(arm_coherent_dma_ops); diff --git a/arch/powerpc/platforms/ps3/system-bus.c b/arch/powerpc/platforms/ps3/system-bus.c index 70fcc9736a8c..3542b7bd6a46 100644 --- a/arch/powerpc/platforms/ps3/system-bus.c +++ b/arch/powerpc/platforms/ps3/system-bus.c @@ -686,18 +686,12 @@ static int ps3_dma_supported(struct device *_dev, u64 mask) return mask >= DMA_BIT_MASK(32); } -static u64 ps3_dma_get_required_mask(struct device *_dev) -{ - return DMA_BIT_MASK(32); -} - static const struct dma_map_ops ps3_sb_dma_ops = { .alloc = ps3_alloc_coherent, .free = ps3_free_coherent, .map_sg = ps3_sb_map_sg, .unmap_sg = ps3_sb_unmap_sg, .dma_supported = ps3_dma_supported, - .get_required_mask = ps3_dma_get_required_mask, .map_page = ps3_sb_map_page, .unmap_page = ps3_unmap_page, .mmap = dma_common_mmap, @@ -710,7 +704,6 @@ static const struct dma_map_ops ps3_ioc0_dma_ops = { .map_sg = ps3_ioc0_map_sg, .unmap_sg = ps3_ioc0_unmap_sg, .dma_supported = ps3_dma_supported, - .get_required_mask = ps3_dma_get_required_mask, .map_page = ps3_ioc0_map_page, .unmap_page = ps3_unmap_page, .mmap = dma_common_mmap, diff --git a/arch/x86/kernel/amd_gart_64.c b/arch/x86/kernel/amd_gart_64.c index a65b4a9c7f87..d02662238b57 100644 --- a/arch/x86/kernel/amd_gart_64.c +++ b/arch/x86/kernel/amd_gart_64.c @@ -680,6 +680,7 @@ static const struct dma_map_ops gart_dma_ops = { .dma_supported = dma_direct_supported, .mmap = dma_common_mmap, .get_sgtable = dma_common_get_sgtable, + .get_required_mask = dma_direct_get_required_mask, }; static void gart_iommu_shutdown(void) diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index cdb157cd70e7..7dff1829c8c5 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -231,25 +231,6 @@ int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma, } EXPORT_SYMBOL(dma_mmap_attrs); -static u64 dma_default_get_required_mask(struct device *dev) -{ - u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT); - u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT)); - u64 mask; - - if (!high_totalram) { - /* convert to mask just covering totalram */ - low_totalram = (1 << (fls(low_totalram) - 1)); - low_totalram += low_totalram - 1; - mask = low_totalram; - } else { - high_totalram = (1 << (fls(high_totalram) - 1)); - high_totalram += high_totalram - 1; - mask = (((u64)high_totalram) << 32) + 0xffffffff; - } - return mask; -} - u64 dma_get_required_mask(struct device *dev) { const struct dma_map_ops *ops = get_dma_ops(dev); @@ -258,7 +239,16 @@ u64 dma_get_required_mask(struct device *dev) return dma_direct_get_required_mask(dev); if (ops->get_required_mask) return ops->get_required_mask(dev); - return dma_default_get_required_mask(dev); + + /* + * We require every DMA ops implementation to at least support a 32-bit + * DMA mask (and use bounce buffering if that isn't supported in + * hardware). As the direct mapping code has its own routine to + * actually report an optimal mask we default to 32-bit here as that + * is the right thing for most IOMMUs, and at least not actively + * harmful in general. + */ + return DMA_BIT_MASK(32); } EXPORT_SYMBOL_GPL(dma_get_required_mask); -- 2.20.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel